My friend had it at a shop in Kansas City. They're saying it needs a BCM. What's the procedure to test the BCM? He's coming home this weekend so I might be able to check it first hand. I will be checking the wiring first in any case.

 

Rarely does the BCM fail. Or the wiring, the switch would be first to inspect and test.

 

The switch/sensor sends a ground signal to the BCM. That triggers the hazard lights.
The switch/sensor sends either a "open" off, or a "ground" on. There is no positive voltage involved.
I don't know how the BCM could possibly be at fault

 

Thank you. I have a replacement switch in hand. I should be able to get it installed tomorrow.